Air fresheners typically are dispensed into the air from devices which have, in combination, a rigid wick, or other transfer means, which contacts, on one end or portion thereof, a reservoir of liquid air freshener and on the other end, or a different portion of the wick, an emanator or diffusion means, which emanator is more porous than the wick means and does not contact the reservoir. It has been found that the porosity of the emanator or other diffusion means has a direct bearing on the effectiveness of the air freshener composition in terms of such factors as duration of use of a fixed quantity of air freshener composition (i.e., evaporation rate) and intensity of vapors emanating from the device (i.e., fragrance intensity).
Known devices of the type contemplated for use with the compositions of the invention are disclosed in U.S Pat. Nos. 4,413,779 and 4,739,928.
U.S. No. 4,413,779 to Santini deals with a vaporizing device for an air freshener composition which device is composed of a rigid nylon wick which contacts a reservoir on one end and a hemispheric diffuser surface which is highly porous on the other.
U.S. No. 4,739,928 which is assigned to Applicant's assignee, deals with an air freshener dispenser which has a wick which contacts both a container of air freshener liquid and a porous emanator pad.
A composition designed for use in a reservoir/wick/emanator device such as that with which Applicant's compositions can be used is described in U.S. No. 4,663,081 (and E.P.O. Publn. No. 194017A1, Appln. 86300604.5) to Grimshaw et al (inventors). That patent describes the same general type of device from which Applicant's composition can be dispensed as well. The compositions disclosed in this patent contain water, diethylene glycol monobutyl ether, and perfume. The glycol ether's volatility assists in the migration of the evaporated air freshener through the wick or other transfer means and to the emanator pad.
As the Grimshaw et al patent points out, the volatility of the volatile component(s) of such a composition must be such that the total composition--including the perfume--reaches the emanator for dissipation into the air. If the volatility of such component(s) is too great, they will evaporate too quickly, leaving the perfume in the reservoir.
Less preferred devices from which the compositions of the invention can be dispensed into the atmosphere are wafer- or pad-like devices U.S. No. 4,367,203 shows such a device. The composition passes through holes or tunnels in the outer or emanator surface(s) of such a device via wick-like action.
Unless otherwise indicated, the disclosures of all of the publications mentioned herein are hereby incorporated by reference.